> I might be wrong, but I've red some articles
> describing the possibility to overclock CPUs
> simply by changing some parameters in uBoot.

That is true for some boxes. But I do believe for the Marvell Kirkwood boards such as this NSA325v2, It is hard to change SAR frequencies entirely in software (unlike the Marvell Armada series). There are Kirkwood MPP pins combo that might work, but I have not been interested in overclocking this box, so don't know for sure.

I think I understand what you mean, as I found another article (http://www.tech-blog.pl/2013/10/24/zyxel-nsa310-overclocking-i-underclocking/) [in polish] describing overclocking NSA310, which however might require some soldering etc. additional work to overclock the CPU.

So, in case the frequency is defined by PLL, [hardware] then, yes, some soldering might be required.

However, if the values are defined in 'uboot_env', then, again, by altering the values it might be possible to overclock the CPU? [Or not, if the kirkwood CPUs have different approach for CPU frequencies, as you described]

Yes, you're correct; the box is NSA325 (v1), and not NSA320. My mistake. Those look quite identical in front, so it's easy to get confused.

ArchLinux config from NSA325v2:

$ zcat /proc/config.gz | grep CONFIG_CPU_FREQ
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_GOV_COMMON=y
CONFIG_CPU_FREQ_STAT=y
CONFIG_CPU_FREQ_STAT_DETAILS=y
CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
# CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND is not set
# CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE is not set
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=y
CONFIG_CPU_FREQ_GOV_USERSPACE=y
CONFIG_CPU_FREQ_GOV_ONDEMAND=y
CONFIG_CPU_FREQ_GOV_CONSERVATIVE=y

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